In recent years, as the population of older people continuously increases due to the extension of the average lifespan, the whole world has rapidly entered into a super-aging society. Several European countries including Japan have already entered into an aging society, and Korea and USA are also entering into the aging society at high speed. In the aging society, strokes, paralyses, and disabled people are tend to increase, and old or feeble people who have weak physical strength and are inconvenient in movement rapidly increase.
Accordingly, there have been developed and used walking assistance systems for supporting daily life such as walking, seating, or standing of old or feeble people or disabled people and assisting their physical strength. A general walking assistance system is configured with wheels, a drive unit, a handle unit, and the like, to operate in a form where a user walks in a desired direction while grasping and pushing the handle unit.
As a walking assistance device stepped forward from the general walking assistance system, there is used an electromotive walking assistance device which is configured in the form of a robot driven and steered by an electric motor. In this case, a user directly manipulates the electromotive walking assistance device so as to move the walking assistance device in a desired direction at a desired speed.
However, general walking assistance devices are mostly manufactured in a structure corresponding to ordinary road surfaces including indoor floor surfaces, flat ground surfaces, and the like. Therefore, these walking assistance devices are weak against rough terrains such as inclined surfaces, prominences, and various obstacles of pavements. That is, when the walking assistance device travels in a fixed form on a rough terrain, there may occur a phenomenon in which the walking assistance device is inclined according to the shape and state of the rough terrain. Accordingly, in the case of an old or feeble user having deficiency in athletic ability, a serious accident such as an overturn accident may be caused according to a degree of force with which the user supports the walking assistance device.
In the case of an existing electromotive walking assistance device, the walking assistance device assists a user to maintain only a minimum balance and does not sufficiently equipped with safety devices provided in consideration of user's safety. For example, there may occur a case where the walking assistance device becomes distant from the user because the user erroneously manipulates the walking assistance device or a case where the walking assistance device collides with the user because the distance between the user and the walking assistance device decreases. Since the main user of the electromotive walking assistance device is an old person or a disabled person, the user may be in danger of injury in the above-described case. Accordingly, a means for ensuring user's walking safety is required.